Initial Commit

pkg/config/config.go

@@ -0,0 +1,142 @@
+package config
+
+import (
+	"encoding/json"
+	"io"
+	"os"
+	"path/filepath"
+
+	"git.cryptic.systems/volker.raschek/civ/pkg/domain"
+	"gopkg.in/yaml.v2"
+)
+
+type FileReader interface {
+	ReadFile() (*domain.Config, error)
+}
+
+func NewFileReader(name string) FileReader {
+	switch filepath.Ext(name) {
+	case ".json":
+		return &JSONReader{
+			name: name,
+		}
+	default:
+		return &YAMLReader{
+			name: name,
+		}
+	}
+}
+
+type FileWriter interface {
+	WriteFile(config *domain.Config) error
+}
+
+func NewFileWriter(name string) FileWriter {
+	switch filepath.Ext(name) {
+	case ".json":
+		return &JSONWriter{
+			name: name,
+		}
+	default:
+		return &YAMLWriter{
+			name: name,
+		}
+	}
+}
+
+type JSONReader struct {
+	name string
+}
+
+func (jr *JSONReader) read(r io.Reader) (*domain.Config, error) {
+	config := new(domain.Config)
+	jsonDecoder := json.NewDecoder(r)
+
+	err := jsonDecoder.Decode(config)
+	if err != nil {
+		return nil, err
+	}
+
+	return config, nil
+}
+
+func (jr *JSONReader) ReadFile() (*domain.Config, error) {
+	f, err := os.Open(jr.name)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	return jr.read(f)
+}
+
+type JSONWriter struct {
+	name string
+}
+
+func (jw *JSONWriter) WriteFile(config *domain.Config) error {
+	f, err := os.Create(jw.name)
+	if err != nil {
+		return err
+	}
+	defer func() { f.Close() }()
+	return jw.write(f, config)
+}
+
+func (jw *JSONWriter) write(w io.Writer, config *domain.Config) error {
+	jsonEncoder := json.NewEncoder(w)
+	jsonEncoder.SetIndent("", "  ")
+
+	err := jsonEncoder.Encode(config)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+type YAMLReader struct {
+	name string
+}
+
+func (yr *YAMLReader) ReadFile() (*domain.Config, error) {
+	f, err := os.Open(yr.name)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	return yr.read(f)
+}
+
+func (yr *YAMLReader) read(r io.Reader) (*domain.Config, error) {
+	config := new(domain.Config)
+	yamlDecoder := yaml.NewDecoder(r)
+
+	err := yamlDecoder.Decode(config)
+	if err != nil {
+		return nil, err
+	}
+
+	return config, nil
+}
+
+type YAMLWriter struct {
+	name string
+}
+
+func (yw *YAMLWriter) WriteFile(config *domain.Config) error {
+	f, err := os.Create(yw.name)
+	if err != nil {
+		return err
+	}
+	defer func() { f.Close() }()
+	return yw.write(f, config)
+}
+
+func (yw *YAMLWriter) write(w io.Writer, config *domain.Config) error {
+	err := yaml.NewEncoder(w).Encode(config)
+	if err != nil {
+		return err
+	}
+	return nil
+}